Centering device for extruding presses



e. H. BRADLEY 2,183,182

cmu'rnnin DEVICE FoR EX'IRUDING PRESSES Filed Dec. 14, 1936 2" Sheets-Sheet 2 3 m a. 2 a 2 F p? l T M .1

Dec. 12, 1939.

wavrrllllv g FIGS A TTORNEYS Federated Dee.

STATES CENTERING DEVICE FOR EXTEUDING PRESSES Guy H. Bradley, Pleasant Ridge, Michl, assignor to Wolverine Tube Company, Detroit, Mich a. corporation of Michigan Application December 14, 1936, Serial No. 115,854

Claims.

This invention relates generally to extruding presses and refers more particularly to improved means for centering a blank or a billet in the holder of the press prior to the extruding opera- 5- tlon.

In accordance with this invention, a billet or a blank is placed in a holder or retainer in seating relation to the extruding die and is upset to not only eliect an intimate contact of the lower end of the billet with the extruding die, but to also bring the side surfaces of the billet in intimate contacting relation with the inner surfaces of the retainer. Thus, the billet is accurately centered in the retainer on the extruding die, and shifting movement thereof during the extruding operation is effectively eliminated.

It is one of the principal objects of this invention to expedite and appreciably simplify the means for upsetting the billets to center the latter with reference to the extruding die, and the several novel features of this means will be made more apparent as-this description proceeds, especially when considered in connection with the accompanying drawings, wherein:

Figure 1 is a fragmentary side elevational view partly in section of an extruding press embodying a centering device constructed in accordance with this invention;

Figure 2 is a plan view of a portion of the centering device shown in Figure 1;

Figure 3 is a cross sectional view taken substantlally on the plane indicated by the line 3-3 of Figure 2;

Figure 4 is a sectional view taken substantially on the plane indicated by the line 4-4 of Figure 2; and

Figure 5 is a sectional view taken substantially on the plane indicated by the line 5-5 of Figure 2.

In general, a blank or billet A, which is preferably preheated to a predetermined temperature, is inserted into a holder or retainer B in seating relation with an extruding die C having a central opening therethrough and having a tapered seat surrounding the opening. After the billet A is placed in the retainer B on the extruding die C, the centering device D is swung to its operative position with respect to the retainer and the billet is upset by this device. As 50 'a result of the upsetting operation, the sides of the billet A are in intimate contacting relation with the inner surfaces of the retainer and the lower end of the billet is deformed to intimately engage the tapered seat on the extruding die 0. Consequently, the billet is accurately centered in the retainer B and lateral shifting movement of the billet, during the extruding operation, is prevented. Upon completion of the upsetting operation, the billet is pierced by the piercing punch E, and the metal of the billet is extruded through the central opening in the die C around the piercing punch E to form the tube.

The centering device 9 is shown in Figure l as hingedly connected to the frame 10 of the press ,for swinging movement in a horizontal plane from an inoperative position, to one side of the piercing punch E, to an operative position above the retainer B in registration with the latter. In detail, the centering device comprises an arm I! having vertically spaced bearings 12 at the outer end thereof rotatahly supported on a vertical shaft 13 having the extremities thereof secured to the frame M by means of the brackets it. The inner end of the arm It carries the upsetting tool assembly l5 and. the elevation of the arm on the shaft l3 is determined to provide for engagement of the annular spacer l5 with the upper end of the retainer B when the tool assembly is swung to the position thereof shown in Figure 1. In this connection, it will be noted that the lower bearing t2 of the arm H rests upon a collar ll pinned to the shaft 83 for movement with the latter as a unit and adapted. to be vertically adjusted by means of a set screw i8 threadedly secured in the bottom bracket id for engagement with the lower end of the shaft 13. Thus, adjustment of the set screw 18 varies the vertical position of the shaft I3 and, accordingly, varies the elevation of the upsetting tool assembly l5 relative to the retainer B.

The upsetting tool assembly 85 comprises a tubular sleeve iii secured to the inner end of the arm H with its axis extending parallel to the axis of swinging movement of the arm and adapted to assume a position in coaxial relationship with the well 20 in the retainer when the arm is swung to its operative position shown in Figure 1. Upon reference to Figure 2, it will be noted that the inner end of the arm H is provided with a vertically extending transversely curved member 2| having a radius of curvature corresponding to the radius of the outer surface of the sleeve l9and is welded, or otherwise permanently secured to this surface of the sleeve. It will be noted from Figure 3 that the lower end of the sleeve extends below the arcuate portion 2| of the arm and is permanently secured to a plate 23 centrally apertured to receive the sleeve. In the operative position of the upsetting tool assembly l5, the plate is supported upon the retainer B by means of the annular spacer is integrally connected to the underside of the plate 23.

The sleeve It] forms a vertical guide for the tool carrying plunger 24 having an axially extending bore 25 therethrough and having an upsetting tool 26 removably secured to the lower end thereof by means of a stud 21. The bore 25 is of suflicient dimension to freely receive the piercing punch E, and the upper end of the plunger 24 is provided with a tapered seat 28 for engagement with the correspondingly tapered lower end portion of an enlargement 23 on the piercing punch E.

The piercing punch E is actuated by a vertically movable ram 30 slidably supported upon the machine frame Ill and actuated by fluid pressure means designated generally by the reference character 3|. The arrangement is such that when the upsetting tool assembly I5 is swung to its operative position with respect to the billet retainer B and the ram 30 is lowered by the means 3|, the enlargement 29 on the piercing punch engages the seat 28 on the upper end of the plunger 24. Upon continued downward movement of the piercing punch by the ram 30, the plunger 24 is moved by the piercing punch downwardly in the sleeve I 9, and the upsetting tool 26 is telescoped within the well 20 of the retainer B into engagement with the billet A. The lower end of the tool 26 is frusto-conical in shape and functions to upset the billet A as the ram 30 continues its downward movement. Inasmuch as the lower end portion of the tool 26 has a sliding fit with the internal surface of the well 20 in the retainer B, metal from the billet is prevented from flowing upwardly and, as a consequence, is forced outwardly and downwardly into intimate contacting relation with the sides of the well and the top surface of the extruding die C. This results in accurately centering the billet relative to the extruding die C and prevents lateral shifting of the billet in the well 20.

Referring again to Figure 3 of the drawings, it will be noted that provision is made for automatically withdrawing the upsetting tool 26 from the well 20 when the ram is returned to its uppermost position. This is accomplished in the present instance by interposing a plurality of springs 32 between the plate 23 secured to the fixed sleeve I3 and the vertically reciprocable plunger 24. In detail, a plurality of vertically extending rods 33 are secured at their lower ends to the plate 23 in concentric relation to the axis of the sleeve IS. The axes of the rods are parallel to the axis oi. the sleeve I9, and the upper ends of the rods slidably engage a plate 34 secured to the upper end of the plunger 24. The springs 32 surround the rods 33 between the plates-23 and 34, with the result that these springs are compressed by the plunger 24 as it is moved downwardly relative to the sleeve l9 to upset the billet A. It will, of course, be understood that when the piercing punch E is returned to its uppermost position by the ram 30, the springs 32 function to move the plunger 24 upwardly and withdraw the upsetting tool 26 from the well 20. It will be noted from Figure 2 that the rods 33 are spaced at equal distances from each other circumferentially of the sleeve l9, and this results in a direct uniform axial movement of the plunger 24 relative to the sleeve IS in an upward direction.

Upon reference to Figure 4 of the drawings, it will be noted that the stroke of the piercing punch E need not be suflicient to clear the plunger 24 when the latter is either swung into or out of registration with the retainer B. As shown in this figure, the leading side of the plunger 24 is provided with a slot 35 therethrough having a width slightly greater than the diameter of the piercing portion of the punch and having a length determined to permit the plunger to be swung out of registration with the retainer B when the piercing punch is moved to the extent required to disengage the upsetting tool 26 from the well 23 of the retainer B. The above arrangement reduces the stroke of the ram 30 to the minimum and this is desirable in that it offers the possibility of reducing the weight, cost and size of the apparatus.

In Figure 5 of the drawings, I have shown means for accurately positioning the upsetting tool assembly IS in operative relation to the billet retainer B prior to the upsetting operation. In detail, a bracket 36 is secured to the bottom of the sleeve [9 and extends laterally outwardly from the sleeve. The outer end of the bracket is provided with a downturned flange portion 31 carrying an adjusting screw 33 having a head portion 39 adapted to engage one side of the billet retainer B when the arm carrying the upsetting tool assembly I5 is swung to its operative position. The screw 38, of course, may be readily adjusted to insure accurately aligning the guide sleeve 13 of the upsetting tool assembly with the well 23 containing the billet A.

Thus, from the foregoing, it will be apparent that I have provided a relatively simple and inexpensive tool assembly capable of being readily moved from an inoperative position out of registration with the billet retainer to an operative position in registration with said retainer. It will also be apparent that I have provided means spaced at equal distances around the axis of the upsetting tool for uniformly withdrawing the latter from the well of the retainer in dependence upon return movement of the actuating ram. This feature is of importance in that it not only prevents binding of the relatively movable parts, but permits accurately fixing the elevation of the arm I l carrying the upsetting tool assembly.

What I claim as my invention is:

1. Apparatus for centering blanks in retainers of extrusion presses having a punch supported for movement into and out of the retainer, comprising an upsetting plunger supported for swinging movement from an inoperative position to a position between the punch and retainer in registration with the latter, said upsetting plunger having a slot through the leading side for receiving the punch upon being swung into registration with the retainer and being supported for movement by the punch into engagement with the blank in the retainer, and spring means spaced around the plunger tensioned by movement of the punch into the retainer and effective upon return movement of the punch to withdraw the plunger from the retainer.

2. Apparatus for centering blanks in retainers of extrusion presses, comprising an arm hingedly mounted for swinging movement from an inoperative position to an operative position, an upsetting plunger carried by the arm in a position to register with the retainer in the operative position of the arm, a spacer element on said arm and engageable with the retainer to prevent cocking of the arm, said spacer element surrounding said plunger and being spaced radially therefrom, and means for moving the plunger into and out of engagement with the blank in the retainer.

8. Apparatus for centering blanks in retainers of extrusion presses, comprising an arm hingedly mounted for swinging movement from an inoperative position to an operative position, an upsetting plunger carried by the arm in a position to register with the retainer in the operative position of the arm, a spacer element on said arm'and engageable with the retainer to prevent cooking of the arm, said spacer element surrounding said plunger and being spaced radially therefrom, and means mounting the plunger on the arm for movement relative to the latter into and out of engagement with the blank in the retainer.

4. Apparatus for centering blanks-in retainers of extrusion presses, comprising an arm, an upsetting plunger mounted on the arm for movement relative to the latter into and out of engagement with the blank in the retainer, means hingedly supporting the arm to permit swinging the plunger into and out of registration with the retainerga spacer element on said arm and engageable with the retainer to preventcocking of the am. said spacer element surrounding said plunger and being spaced radially therefrom, and yieldable means spaced equal distances from each other around the plunger for withdrawing the latter from the retainer.

5. Apparatus for centering blanks in retainers of extrusion presses having a reciprocable member, comprising an arm, an upsetting plunger mounted on the arm for movement relative to the latter by said member into engagement with the blank in the retainer, means hingedly supporting the arm to permit swinging movement of the plunger into and out of registration with the retainer, a spacer element on said arm and engageabie with the retainer to prevent cocking 'of the arm, said spacer element surrounding said plunger and being spaced radially therefrom, and a plurality of springs carried by the arm in spaced relation to each other around the plunger and acting on the latter when the member is in its return movement to withdraw the plunger from the retainer.

GUY H. BRADLEY. 

